
Description
The ecm continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check ensures that the ecm is functioning properly. If any malfunction is detected, the ecm sets the appropriate dtc and illuminates the mil.
The ecm memory status is diagnosed by internal mirroring of the main cpu and the sub cpu to detect random access memory (ram) errors. The two cpus also perform continuous mutual monitoring. The ecm illuminates the mil and sets a dtc if: 1) outputs from the two cpus are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ecm malfunction is found.

Monitor strategy

Typical enabling conditions
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Typical malfunction thresholds


Inspection procedure
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

System voltage
Starter relay circuit highArmrest
Fold down the armrest for use.
NOTICE
â– To prevent damage to the
armrest
Do not apply too much load on the
armrest.
Assist grips
An assist grip installed on the
ceiling can be used to support
your body while sitting on the
seat.
WARNING
â– Assist grips
Do not use the assist grip when
getting in o ...
If you think
something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your toyota dealer as
soon as possible.
Visible symptoms
Fluid leaks under the vehicle
(water dripping from the air conditioning after use is normal.)
Flat-looking tires or uneven tire w ...
Removal and installation of engine intake parts
If any metal particles enter inlet system parts, they
may damage the engine.
When removing and installing inlet system parts,
cover the openings of the removed parts and engine
openings. Use gummed tape or other suitable
materials.
When installing inlet system parts, check that no ...